<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8" />
	<title>JavaScript</title>
	<script type="text/javascript">
	
	</script>
</head>
<body>
    <script type="text/javascript">
	    <!-- 声明变量 -->
		var numble1;
		var numble2;
		var numble3;
		var numble4,numble5,numble6;
		
		<!-- 给变量赋值 -->
		numble1 = 120;
		numble2 = 130;
		numble3 = 223;
		
		<!-- 基本运算 -->
		numble4 = numble1 - numble2;
		numble5 = numble3 + numble2;
		numble6 = numble1 * numble2;
		
		<!-- 输出结果 -->
		
		console.log(numble4);  <!-- 控制台输出 --> 
		alert(numble5);   <!-- 浏览器弹出 -->
		document.write(numble6);   <!-- 页面显示 -->
		
		
	</script>
</body>
</html>
